La Plata Property Overview
The road accessible La Plata project covers 44 Sq Km within the historic high-grade La Plata mining district located at the southwest end of the prolific Colorado Mineral Belt. Mineralization is related to a large-scale precious metals + platinum group element (PGE) alkaline porphyry Cu system with associated high-grade Ag and Au epithermal vein and replacement deposits.
Following a $6.3 Million strategic equity investment by Newmont Mining in May 2023,1 Metallic Minerals announced an updated NI 43-101 Inferred Mineral Resource Estimate for the project within the central Allard Cu-Ag porphyry deposit (July 2023).2 The Company acquired the project in 2019 and has defined an Inferred Mineral Resource of 1,317 Mlbs of CuEq consisting of 147.3 Mt at an average grade of 0.41% CuEq (0.37% Cu and 3.72 g/t Ag) using a 0.25% CuEq cut-off grade..2
The Allard deposit remains open to significant expansion within the resource area and the greater La Plata Cu-Ag-Au-PGE project remains underexplored and open to new discoveries of both additional Cu porphyry centers as well as high-grade epithermal Ag and Au systems.
Project Highlights
2023 drillingwas focused on further resource expansion and follow-up on drill hole LAP22-04 which was the longest and highest-grade hole ever encountered at the project, intercepting of 816.0 m of 0.41% recovered CuEq (0.30% Cu, 2.47 g/t Ag, 0.04 g/t Au, 0.06 g/t Pt and 0.09 g/t Pd)3. LAP22-04, ended in mineralization with the last 5.2 m returning of 5.39% recovered CuEq with elevated precious metals and PGEs (2.44% Cu, 18.7 g/t Ag, 0.47 g/t Au, 1.76 g/t Pt and 2.78 g/t Pd)3.
The 2023 Resource area incorporates a single porphyry intrusive-hosted sulphide system that is drill defined over a kilometer in length, 400 m in width and to greater than a kilometer of vertical extent and remains open to expansion in all directions. The resource area shows strong spatial correlation with large-scale anomalies in geophysics, spectral imagery and metal in soil values, providing a compelling basis for extensive further resource expansion and for potential new discoveries in future drill campaigns.
In addition to the current resource, 16 untested potential porphyry centers have been identified on the greater La Plata project area, as well as target areas with potential for significant high-grade epithermal Ag and Au.
Historical production from some of these high-grade structures exceeded 1,000 g/t Ag and over 15 g/t Au with some of the richest deposits delivering true bonanza grades for Ag and Au4.
Project History
The La Plata district has a long and rich history of mining with the first Ag deposits discovered in the 1700s by Spanish explorers. High-grade Ag and Au production has been documented from the 1870s through the early 1940s from vein structures, replacement bodies and breccia zones at over 90 individual mines and prospects. From the 1950s to 1970s, major miners Rio Tinto, Exxon and Freeport-McMoRan explored in the district focusing on the significant potential for bulk-tonnage disseminated and stockwork porphyry-hosted Cu mineralization.
Freeport-McMoRan retained ownership of claims in the district until 2002 when they sold their holdings to the current underlying vendors during the lows of the last metal price cycle.
A total of 25,532 m in 88 drill holes have been drilled on the property since the 1950s and have confirmed the presence of a large-scale, multi-phase porphyry system with significant Ag, Au and Cu. This large-scale mineralized system is associated with a 10 sq km, strong magnetic signature with intense hydrothermal alteration mapped in satellite based multispectral imaging.
The Allard deposit is a significant potential source of Cu, Ag, Au, and Pt group metals, important for the modernization and electrification of the economy. In addition, the broader La Plata property is known for occurrences of tellurium (Te) and rare earth elements, as Critical Minerals that are important to meet the increasing demand for green energy. Te was produced as a by-product of historic high-grade Au and Ag production in the district. These and other important metals noted in the district will be evaluated as part of ongoing exploration of the project.
Work during the 2022 field season focused on the Allard target area with the completion 1,730 m of expansion drilling and resulted in the intersection of one of the top intervals for a North American Cu project over the last several years. Metallic Minerals is the first company to complete significant exploration on the La Plata project in nearly 50 years. Since acquisition, the Company has systematically explored the project by employing an array of modern exploration techniques. Through this work the Company has identified new high-grade epithermal-style targets and over 16 potential porphyry style mineralized zones across the broader property including at the adjacent Copper Hill target area, 1 km east from the Allard deposit and the Morning Star target 1 km to the west.
The 2023 exploration and drill campaign included 4,530 m in four diamond drill holes with the dual objectives of expanding on the existing and defining the controls to higher-grade mineralization as seen in drill hole LAP22-04. All four 2023 holes intersected porphyry-style mineralization starting from surface and continuing over their entire lengths (up to 1,350 m). Three of four holes intercepted continuous porphyry style Cu-Ag-Au-PGE mineralization over 500 m in width at 0.3% Cu including significant intervals exceeding 0.5% to 0.7% CuEq with associated Ag, Au and PGEs. Drill hole LAP23-05 intersected 909.0 m of continuous mineralization from surface grading 0.26% recovered CuEq (0.21% Cu, 1.55 g/t Ag, 0.04 g/t Au, 0.02 g/t Pt and 0.03 g/t Pd) over the entire hole length, with a 550.0 m wide higher-grade zone.3
An important objective in 2023 and 2024, was to identify, advance and explore new priority targets outside of the Allard resource area. Significant high-grade results were received in surface rock samples taken from more than 20 different target areas during the 2023 field season as part of a district-scale surface mapping initiative. Work in 2024 consisted of field mapping and soil and rock sampling to refine and enhance these additional targets with three of these areas having advanced to a drill testing stage. Additional work in 2024 included an increase of community engagement activities and expanded permitting and environmental efforts to build a solid foundation for future project development.
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